Current technology available for cutting, using diamond wire can be categorized into three categories.
In a first category, cutting is accomplished using a pulley system and guide wheels. This technology is mainly used on shore and has the disadvantage that for large sections, the guide wheels will need to be re-positioned and the wire will have to be shortened at regular intervals through the cutting operation.
In a second category, cutting is accomplished using diamond wire saws with clamp. These clamp saws are efficient, but has the main disadvantage that they only fit a small range of diameters and that the tool has to be bigger than the diameter you cut, due to the need for clamp.
In a third category, cutting is accomplished using a cart with diamond wire mounted on the cart. By only mounting the diamond wire on the cart itself, only the circumference can be cut, not the through section. Further this technology will not allow for cuts on a straight or inverse curvature surface. Further it requires a track, custom built to the diameter of the section to be cut.
One issue that arises with these systems is that they are not easily useful when cutting large size structures (>4 m outer diameter) subsea.